This invention relates generally to improved apparatus for the production of caseless (skinless) sausage, and more particularly to a reusable tubular casing and associated apparatus for this purpose.
In original sausage making procedures, bulk sausage was injected into a natural intestine casing and subsequently subjected to cooking and smoking procedures required for producing a particular type of sausage. Artificial casings made of various materials have also been utilized for quite some time. Most of the natural and artificial casings are inedible and hence must be removed before consumption. Accordingly, it has become the practice to peel the sausage casing during production. The casings are therefore not reusable, but are peeled and discarded prior to the completion of the production process.
Generally speaking, the process requires relatively expensive and specialized machinery as well as a considerable number of manual operations. For example, sausage stuffing is relatively automated utilizing grinders, cutters, emulsifiers and bonders to batch the material, and fill the casings. However, some sausages, particularly large diameter types are still hand or manually filled into the casings.
Generally speaking, the casing material is used as a vehicle for holding the relatively soft and unstable sausage material during initial smoking and/or cooking or other heat treating steps. Thereafter, the smoked and/or cooked casing-enclosed material is water showered and chilled, stabilizing the consistency and shape of the sausage. Thereafter, the stabilized links are generally hand-fed into a peeler for removal of the casing material prior to any further processing. The manual labor involved in the peeling of casing, in addition to being relatively expensive, also accounts for the largest percentage of breakage, spoilage, etc. of the sausages. This is so, in part, because it is impossible to precisely adjust the cutting portions of the peeling machines to avoid frequent cutting into the surfaces of the sausages. Hence, a relatively high precentage of sausages are scored or cut, resulting in bursting when the sausage is thereafter heated, whereupon the sausage must be discarded. Additionally, following the removal of the casing material, the material is no longer usable and is discarded. Hence, a relatively large amount of casing material is required at a significant expense in the production of large quantities of sausage.
In an effort to avoid many of the foregoing problems, a number of processes and related apparatus have been developed for production of so-called caseless or skinless sausages. These processes generally employ an apparatus provided with a plurality of molds which receive the sausage material for the initial forming and cooking steps of the procedure. Thereafter, the formed and cooked sausage is removed from the molds whereupon the molds may be cleaned for reuse. Hence, the molds are generally carried on a suitable conveyor mechanism through various stations in a mechanized process including a fill station, a boiling or cooking oven, a cooling station and a mold removal station.
However, the foregoing mold structures have generally left much room for improvement. For example, during the heating and cooking of the bulk sausage material, a quantity of water vapor, steam and other volatile substances are released from the material and provision must be made for their release from the mold as well. Additionally, the inner surface of the mold must readily and rapidly release the sausage material substantially without sticking when the heating and cooling process is completed. Moreover, the pressure created during heating due to the expansion of the bulk sausage material can prevent vapor and other volatile substances released during cooking from reaching exits provided in the casings or molds. Also, this expansion of the bulk sausage material often results in discontinuities of the pressure applied throughout the material, which results in undesirable discontinuities in the density of the completed sausage.
Briefly, then, reusable casings for the production of a caseless sausage must meet the following requirements:
1. The casing must be sufficiently permeable for release of water vapor steam and other volatile components released during cooking.
2. The casing must not release any constituents injurous to health or adversely affect the taste, smell or appearance of the sausage. In this latter regard, pores provided in the above-mentioned molding apparatus often produce undesirable markings on the surfaces of the completed sausage.
3. The pores of the casing must be relatively resistant to being plugged with fat or the like released during cooking so that the permeability of the casing is not decreased.
4. The casing must be adapted to be relatively simply and rapidly cleaned between uses.
5. The casing must be resistant to damage from the pressures, temperatures, etc., encountered during cooking, and remain mechanically stable and pliant through a relatively large number of uses.
6. The internal surfaces of the casing must neither adhere to the sausage material nor cause disfiguration or discontinuities of the external surface of the finished sausage, which should have a smooth, unbroken appearance.